Relay



C. W. BURROWS.

RELAY.

APPLICATION FILED MAR.13.1918.

,329,578. Patented Feb. 3, 1920.

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C. W. BUBROWS.

RELAY.

APPLICATION FILED MAR-13,1918.

1,329,578. Patented Feb. 3,1920.

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admin 4 We BY Z M A 'I'TOANEY.

CHARLES W. BURROWS, OF WASHINGTON, DISTRICT OF COLUMBIA.

i RELAY.

Application filed March 13, 1918.

To all whom it may concern.

Be it known that I, CHARLES W. BURROWS, a citizen of the United-States, residing in the city of Washington, District of Columbia, have invented certain new and useful Improvements in Relays, of which the following is a specification.

My invention relates to electromagnetic relays, and particularly to relays designed to be operated by direct current. More particularly, the invention relates to relays of this character the armature or ,movable member of which is arranged to assume three functional positions, viz., an intermediate position when the relay is denergized and one extreme position or another according as th relay is energized by current flowing in one direction or the other.

I will describe one. form of relay embodying my invention and will then point out the novel features thereof in claims.

In the accompanying drawings, Figure 1 is a view showing in vertical section one form of relay embodying my invention, the section being taken'on the line I-I of Fig. 2 looking in the direction indicated by the arrows. Fig. 2 is a view showlng in end elevation the relay shown in Fig. 1. Fig. 3 is a horizontal sectional view of the relay shown in the preceding views the section being taken on the line III-III of Fig. 1, looking in the direction indicated by the arrows. Fig. 4 is a view showing more clearly the armature A shown in the preceding views. Fig. 5 is a viewshowing the armature A in end elevation. Fig. 6 is a view showing part of th core and one of the polepieces of the electromagnet E shown in Flgs. 1, 2 and 3.

Similar reference characters refer to similar parts in each of the several views.

Referring first to Figs. 1, 2 and 3, the relay includes an electromagnet E, comprising as usual, two parallel cores 1 and l carrying coils 3 and'3 respectively, a backstrap 2, and two pole-pieces 4 and 4 attached to the cores 1 and 1 respectively. As shown in Fig. 6, each pole-piece 4 and 4 is circular in form, and, as shown in Fig. 2, each of these pole-pieces is set into a recess cut in the lower end of the core and is attached to the core by screws 5.

Located between the pole-pieces 4 and 4 are two other soft iron pole-pieces 6 and 6 the confronting faces of which are concave in form, as shown in Fig. 1, to provide a Specification of Letters Patent.

' Patented Feb. 3, 1920. Serial No. 222,095.

cylindrical field which receives the armature A hereinafter described. These two pole pieces are held in proper spaced relation by two brass plates 7 and 7 which are attached he pole-pieces by means of screws 8, as is best shown in Fig. 1. These brass plates also serve to support the pole-pieces 6 and 6 in proper relation to the electromagnet. To accomplish this I provide four angle members 9 and 9*, preferably of brass, one leg of each member being attached'to plate 7 or 7 by screws 10; the other leg of each angle member 9 is attached to pole-piece 4 by screws 11, and the other leg of each angle member 9 is similarly attached to pole-piece 4*. It will be seen, therefore, that the electromagnet E and the pole-pieces 6 and 6 constitute parts of a rigid structure.

The pole-pieces 6, 6 are constantly polarized by means of U-shaped permanent magnets P, each of which has one pole in contact with pole-piece 6 and the other pole in contact with pole-piece 6. For purposes of this specification I will assume that polepiece 6 is north and pole-piece 6 is south.

Located in the space between pole-pieces 4, 4", and 6 and 6 is the armature A. This armature. as best shown in Figs. 4 and 5, comprises two L shaped members 12 and 12, both of soft iron. placed together as shown in Fig. 4 to form a rectangle. Interposed between the members 12 and 12 are strips 13 and 13 of non-magnetizable material, such as brass, so that the armature forms a path of high reluctance for the flow of magnetic flux from member 12 to member 12 and vice versa. The two members andthe brass strips are held together by means of screws 14. The ends of the armature are circular, as shown in Fig. 5, and the general shape of the armature is cylindrical, the diameter being slightly less than the diameter of the gap between pole-pieces 6 and 6*, so that the armature fits into this gap with sutlicient clearance to avoid possibility of sticking. Located at the center of each circular end of the armature is a pivot hole 16 whereby the armature may be mounted on pivot screws 15 and 1? which pass through the pole-pieces 4 and 4 respectively. These pivot screws are in the axial line of the cvlindrical gap between pole-pieces 6 and 6?. hence the armature is pivotally mounted to oscillate on such axial line.

It will be seen that the electromagnet .E constitutes means for passing magnetic flux in the winding 3, 3

- for passing flux through the armature in an axialdirection, and that this flux is in one direction or the other according to the direction of current .nets' P, on the other hand constitute means through the armature at right angles to the flux created by the electromagnet. These fluxes act on the armature in the following manner:

Assuming first that the electromagnet is deenergized, the flux created by the permanent magnets will tend to place the armature in the position in which it is shown in Fig. 1 (or at 180 from this position), because this is the position wherein the reluctance of the path between pole-pieces 6 and 6 is lowest. I will term this the intermediate position of the armature. It may be desirable in some cases to bias the armature to this position by other suitable :means. Remembering that pole-piece 6 is north and pole-piece 6 south, I will now assume that the electromagnet becomes energized in such direction that pole-piece 1 is north and polepiece 45 is south. Armature member 12 then becomes a north pole and member 12 a south pole, so that member 12 is attracted toward pole-piece 6 and is repelled from pole-pieceflfi, whereas member 12 is attracted toward pole-piece 6 and repelled from pole-piece 6 The armature then swings in counter-clockwise direction, as viewed in Fig. 1. If, on the other hand, the

electromagnet is energized in the reverse direction, so that pole-piece 4: becomes south and pole-piece 4 north, the forces actlng on the armature will be reversed for reasons.

which will be apparent without further explanation, so that the armature will then swing 1n clockwise direction, as viewed in Fi 1 Armature A may be employed to control one or more contacts in any desired manner. For example, as shown in Fig. 1, the arma ture is operatively connected with a contact member 17, which, when the armature is in its intermediate position, engages with a fixed contact 18. When the armature swings in counterclockwise direction from the position in which it is shown in Fig. 1, con-. tact member 17 moves away from contact 18 and engages with a fixed contact 20. IV-hen the armature swings in clockwise direction from the position in which it is shown in Fig. 1, contact member 17 engages with a fixed contact 19.

The control of the winding 3, 3 of electromagnet E may be accomplished in any desired manner. As here shown, this winding is supplied with current from a battery B, and its circuit is controlled by a pole-changing switch S. Then the switch S is in the intermediate position, as shown in Fig. 2, the electromagnet E is denergized, whereas the electromagnet is ener- The permanent magture located between said gized in onedirection or the other according as the switch S is thrown to one extreme position or the other.

Although I have herein shown and described only one form of relay embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my I claim is:

1. A relay comprising two confronting pole-pieces of soft iron, a permanent magnet for polarizing said pole-pieces, an armature located between said pole-pieces and pivotally mounted on an axis passing midway between them, said armature comprising two soft iron L-shaped members placed together to form a rectangle with strips of non-magnetizable material between them, an electroinvention, what magnet having pole-pieces located adjacent when the two armature members bridge the gap between said first-mentioned pole-pieces,

and two other contacts controlled by said armature one or the other of which is closed according as the armature swings in one direction or the other from said bridging position.

' 2. A relay comprising a permanent magnet having confronting pole-pieces, an armapole-pieces and pivotally mounted on an axis passing midway between them, said armature comprising two soft iron L-shaped members placed together to form a rectangle with strlps of non-magnetizable material between them, an electromagnet having pole-pieces located adjacent the axial ends of said armature, a contact controlled by said armature and closed only when the two armature members bridgethegap between said first-mentioned pole-pieces, and two other contacts controlled by said armature one or the other of which is closed according as the armature. swings in one direction or the other from said bridging position.

3. A relay comprising a pair of confronting pole-pieces, an armature located between said pole-pieces and pivotally mounted on n ax s passing midway between them, said armature comprising two soft iron L-shaped members placed together to form a rectangle with strips of non-magnetizable material between them, another pair of pole-pieces located adjacent the axial ends of said armature, means for constantly polarizing one of said pairs of pole-pieces, means for reversibly polarizing the other pair of pole-pieces, a contact controlled by said armature and closed only when the two armature members bridge the gap between said first-mentioned pole-pieces, and two other contacts controlled by said armature one or the other of which is closed according as the armature swings in one direction or the other from said bridging position.

' 4. A relay comprising a pair of confronting pole-pieces, an armature located between said pole-pieces and pivotally mounted on an aXis passing midway between them, said armature comprising two soft iron L-shaped members placed together to form a rectangle with strips of non-n'iagnetizable material between them, another pair of pole-pieces located adjacent the axial ends of said-armature, a permanent magnet for polarizing one of said pairs of pole-pieces, an electromagnet for polarizing the other pair of pole-pieces, a contact controlled by said armature and .closed only when the two armature members bridge the gap between said first-mentioned pole-pieces, and two other contacts controlled by said armature one or the other of which is closed according as the armature swings in one direction or the other from said bridging position.

5( A relay comprising an armature constituting two soft iron L-shaped members placed together to form a rectangle with strips of non-magnetizable material between them, said armature being pivotally mount ed on an axis passing through the middle points of two opposite ends thereof, means for passing magnetic flux through said arnature in axial dlrection, means forpassing magnetic flux through said armature at substantially right angles to the first flux, a

contact controlled by said armature and CHARLES W. BURROWS.

Witnesses MAUD MURoooK BURRows, B. T. WEBSTER. 

